The resignation of UN prosecutor Robert Petit from the Khmer Rouge tribunal will reverberate through the court’s proceedings, leaving an absence of leadership and the likelihood of more delays, local and international observers say.

Petit will leave the tribunal Sept. 1, as the UN-backed tribunal is in the midst of its first trial, for jailed Khmer Rouge prison chief Duch. Petit announced in June he was leaving for personal reasons. He had pushed for at least six more indictments at the court, to add to the five former leaders already on trial, and he had steered the UN prosecution throughout the initial arrests and charges of five former leaders of the regime.

“Petit’s departure creates an urgent need for leadership in the Co-Prosecutor’s Office,” James Goldston, executive director of the Open Society Justice Initiative, which has a court monitoring project, told VOA Khmer. “The next case, of four accused involving multiple crimes, is complex. Concerns are already arising about the length of time the investigation is taking.”

That case, No. 002, will try the four senior-most leaders of the regime, its chief ideologue Nuon Chea, head of state Khieu Samphan, foreign minister Ieng Sary and his wife, social affairs minister Ieng Thirith.

“A high-caliber leader in the prosecutor’s office is essential to ensure that this case is prepared for trial as soon as possible,” Goldston said.

Not only could that case be delayed, but the trial of Kaing Kek Iev, better known as Duch, who is facing multiple atrocity crimes charges for his role as head of Tuol Sleng prison, could also slow.

“If he’d left when the Duch trial was finished, there probably would not be a problem,” said Sok Sam Oeun, head of the Cambodian Defenders Project, which provides free legal services to Cambodians. “But when Duch’s case has not yet been completed, that can lead to problems for the next prosecutor.”

However, Petit is not leaving an empty office behind him, and some observers contend that the groundwork he laid will help his incoming replacement.

David Tolbert, a former special adviser to the tribunal and now at the US Institute for Peace, said Petit had served well in a challenging environment and was leaving behind an office that was well prepared for Duch’s trial and the trials ahead.

“On the international side, major strategic decisions have largely been made and can be implemented by the current team and the new co-prosecutor,” he said.

Caitlin Reiger, deputy director of the International Center for Transitional Justice, another tribunal monitor, noted that Petit’s departure won’t hurt the process, as long as it keeps moving and the UN and the government quickly appoint a replacement.

“What is most important is to have someone who is experienced with these types of cases, has a strong reputation for independence and understands the challenges facing the [tribunal],” Reiger said.

The next prosecutor should continue outreach for victims and ensure the court leaves “a positive legacy for the rule of law,” she said.

The tribunal has been dogged by allegations of corruption and mismanagement, and wrangling between the UN and Cambodian judges and prosecutors, even before a single suspect was arrested.

Cambodian staff have complained they pay kickbacks to high-ranking officials, and Petit’s counterpart, judge Chea Leang, has faced criticism for making what appear to be politically motivated decisions, following her rejection of Petit’s proposal to indict more suspects.

Chea Leang has said more indictments would destabilize the country, echoing remarks of Prime Minister Hun Sen that critics say are not grounded in legal criteria.

With Petit leaving, national judges may not work independently, said Kek Galabru, founder of the rights group Licadho.

“The resignation of an international co-prosecutor affects the reputation of the court,” she said, “and raises a lot of questions.”